Micromechanical mirrors are suitable for a large number of applications, for example microprojectors or lidar devices.
In United States Published Patent Appln. No. 2011/0002022, a method is described for adapting a resonance frequency of an optical scanner. In this document, an optical scanner is described that has a main substrate body having two cantilevers, a drive device, a mirror segment, and a clamping device. The mirror segment is structured out from the main substrate body and is suspended between the two cantilevers. The mirror segment can be displaced relative to the clamping device by exciting the main substrate body with a resonance frequency. The resonance frequency is adapted through constructive modifications of the main substrate body and/or of the clamping device.
In such optical scanners, the maximum mirror surface of the mirror segment can be limited due to dynamic inherent deformations that result from the increasing moment of inertia of the mirror surface at a high resonance frequency. Standardly, for applications a maximum deformation of the mirror surface on the order of magnitude of 10% of the wavelength of the light that is to be reflected is tolerated.